A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 4140-01-367-0791
NSN 4140-00-155-8012
NSN 5996-01-377-8219
NSN 6150-01-593-0142
NSN 5895-00-082-3925
NSN 5975-01-512-8525
NSN 5905-00-706-7452
NSN 6150-01-312-4179
NSN 6105-01-428-9648
NSN 6105-01-092-6770
NSN 6220-01-612-5894
NSN 5996-00-766-0814